The longest-running search for ra­di­o sig­nals from al­ien civ­il­iz­a­tions is get­ting a burst of new data from an up­grad­ed tel­e­scope.

That means dramatically im­proved search ca­pa­bil­i­ties, proj­ect sci­en­tists say—but the full ben­e­fits will be real­ized only with pub­lic par­ticipa­t­ion. They’re are call­ing for new vol­un­teers for SETI@home, a proj­ect in which or­di­nary cit­i­zens do­nate un­used time on their com­put­ers to let the machines help comb through the search da­ta.

“The next genera­t­ion SETI@home is 500 times more pow­er­ful then an­y­thing an­y­one has done be­fore,” said proj­ect chief sci­ent­ist Dan Wer­thi­mer. “That means we are 500 times more likely to find” al­ien life—if enough new vol­un­teers join. Even if not, the up­grades still prom­ise an im­prove­ment of at least about 100-fold, he said.

Since it launched eight years ago, the Un­ivers­ity of Cal­i­for­nia, Berkeley-based SETI@home has signed up more than 5 mil­lion in­ter­est­ed vol­un­teers, ac­cord­ing to proj­ect sci­en­tists. It boasts the larg­est com­mun­ity of ded­i­cat­ed users of any In­ter­net com­put­ing proj­ect, they said: 170,000 devo­tees on 320,000 com­put­ers. This num­ber of com­put­ers should rise by an ad­di­tion­al mil­lion to han­dle the ex­pand­ed da­ta flow, Wer­thi­mer said.

SETI stands for Search for Ex­tra­ter­res­tri­al In­tel­li­gence. Pro­s­pec­tive vo­lun­teers are be­ing asked to visit the SETI@home web­site for in­for­ma­tion.

The in­creased amount of da­ta is a re­sult of new and more sen­si­tive re­ceivers and oth­er im­prove­ments to the world’s larg­est ra­di­o tel­e­scope in Are­ci­bo, Puerto Rico, said proj­ect lead­ers. The soft­ware used for the job, they added, has been has been up­grad­ed to deal with the surge of in­for­m­a­tion.

Ac­cord­ing to proj­ect sci­ent­ist Er­ic Ko­r­pela, the new da­ta amounts to 300 gi­ga­bytes per day; on a yearly basis that adds up to the amount of da­ta stored in the U.S. Li­brary of Con­gress. “That’s why we need all the vol­un­teers,” he said. “Ev­ery­one has a chance to be part of the larg­est pub­lic-par­ticipa­t­ion sci­ence proj­ect in his­to­ry.”

The 1,000-foot wide Are­ci­bo dish, which fills a val­ley in Puerto Rico, is part of the Na­t­ional As­tron­o­my and Ion­o­sphere Cen­ter ope­rated by Cor­nell Un­ivers­ity in Ith­a­ca, N.Y. Since 1992, Wer­thi­mer and his team have used ra­di­o ob­serva­t­ions at Are­ci­bo to rec­ord sig­nals from space and an­a­lyze them for pat­terns that could in­di­cate they were trans­mit­ted by a civ­il­iz­a­tion.

When the team’s in­com­ing da­ta over­whelmed its abil­ity to an­a­lyze it, the sci­en­tists con­ceived a “dis­tributed com­put­ing” proj­ect to har­ness many com­put­ers in­to one big supe­rcomputer to do the anal­y­sis. Since SETI@home was launched, oth­er dis­trib­ut­ed com­put­ing proj­ects have aris­en, from fold­ing@home to pre­dict the struc­tures of or­gan­ic molecules, to the newly-launched cos­mol­o­gy@home to mod­el pos­si­ble un­iverses. Most share the SETI@home plat­form.

“Un­til now, there has been enough com­put­ing pow­er to go around,” Wer­thi­mer said. What largely trig­gered the new flow of da­ta was the ad­di­tion of sev­en new re­ceivers at Are­ci­bo, which let the tel­e­scope rec­ord sig­nals from sev­en re­gions of the sky sim­ul­ta­ne­ous­ly in­stead of one, he added.

“The mul­ti­ple re­ceivers help us weed out in­ter­fer­ence bet­ter” and re­duce the chance of mis­tak­ing earthly sig­nals from al­ien ones, he said. No tell­tale sig­nals from an in­tel­li­gent civ­il­iz­a­tion have yet been iden­ti­fied.

“Earth­lings are just get­ting started look­ing at the fre­quen­cies in the sky; we’re look­ing only at the cos­mic­ally bright­est sources, hop­ing we are scan­ning the right ra­di­o chan­nels,” Wer­thi­mer said. “The good news is, we’re en­ter­ing an era when we will be able to scan bil­lions of chan­nels. Are­ci­bo is now op­ti­mized for this kind of search, so if there are sig­nals out there, we or our vol­un­teers will find them.”

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The world's larg­est single-dish ra­di­o tel­e­scope, the Are­ci­bo Ob­serv­a­to­ry in Puerto Rico is one of the larg­est cen­ters for re­search in ra­di­o as­tron­o­my. The huge "dish" is 1000 feet (305 me­ters) wide, 167 feet (51 me­ters) deep and co­vers about 20 ac­res (0.08 square km). (Cred­it: NAIC Are­ci­bo Ob­serv­a­to­ry/NSF)